Garden Hotline: Encouraging beneficial insects

KEITH FULLERHorticultural Consultant

Published Saturday, July 17, 2004

Summertime can be a challenge to Florida gardeners. One of the battles that must be waged is to keep damaging insects at bay. One battle strategy to employ in this war is to entice predators to fight on your behalf.

One of the best known beneficial insects is the ladybug. You can invite these ladies into your landscape by incorporating their favorite plants into your garden. Yarrow, butterfly weed, marigolds and tansy are a few of their favorites.

Learn to identify the immature ladybug as they look nothing like the adult, but eat more insects than the mature form. Immature ladybugs are multisegmented black and yellow insects. Each may consume several hundred aphids, earning them the name aphid wolf. Green lacewing larvae can devour aphids, mites, scale, immature whiteflies and insect eggs. Adult lacewings tend to be pollen and nectar eaters, but the appetites of the immature insect is voracious.

Plant specific flowers in the garden to entice the adults to linger and reproduce. Red cosmos, coreopsis, golden rod and Queen Anne's lace are recommended favorites of green lace wings.

There are many beneficial insects that to us appear uninteresting or which are inconspicuous. Parasitic wasps, predatory wasps, syrphid flies, tachinid flies and ground beetles are all predatory insects. Some will consume other insects, while others lay eggs on other insects and their offspring will consume its host.

Plants with small flowers often help to support predatory insects. Wildflowers, daisies and strawflowers are ideal. An occasion piece of over ripe fruit left in the landscape will also help to entice beneficial insect activity.